Device for fixing a switch unit in a keyboard switch

ABSTRACT

A device for fixing a switch unit into a keyboard switch. The switch unit is rectangular and has at least one stopper projected at one upper corner thereof, a knob engaging portion formed at the upper center thereof, and a pair of projections formed at opposite side surfaces thereof. A keyboard plate formed in a U shape has a plurality of bridge portions and a pair of cutouts for engaging the projections of the switch unit to fix the switch unit therein. A keep leaf spring having a center hole for turnably engaging the knob engaging portion of the switch unit is held under the bridge portions of the keyboard plate at opposite ends thereof when turned in longitudinal direction of the keyboard plate and is used to hold the switch unit into the keyboard switch.

United States Patent Yanaga Nov. 28, 1972 [54] DEVICEFOR FIXING A SWITCH UNIT 2,998,500 8/ 1961 Di Carlo ..200/168 B IN A KEYBOARD SWITCH 3,337,708 8/1967 Cerveny et a1. ..200/168 C [72] Inventor: Makoto Yanaga, Tokyo, Japan Primary Examiner H. 0. Jones [73] Assignee: Alps Electric Co., Ltd., Tokyo, AttomeyRichard C. Sughrue et al.

Japan [22] Filed: Jan. 25, 1972 [57] ABSTRACT A device for fixing a switch unit' into a keyboard [21] Appl' Q switch. The switch unit is rectangular and has at least one stopper projected at one upper comer thereof, a [30] Foreign Application Priority Data knob engaging portion formed at the upper center thereof, and a pair of projections formed at opposite Jan. 25, 1971 Japan ..46/2734 Side Surfaces thereofl A keyboard plate formed in a U shape has a plurality of bridge portions and a pair of cutouts for engaging the projections of the switch, unit to fix the switch unit therein A keep 1e af spring [58] Field of Search ..200/168 R, 168 B, 168 C ing a center hole for tumably engaging the knob gaging portion of the switch unit is held under the [56] References Clted bridge portions of the keyboard plate at opposite ends UNITED STATES PATENTS thereof when turned in longitudinal direction of the keyboard plate and is used to hold the switch unit into 2,522,172 9/ 1950 Gates ..200/168 C the keyboard Switch v 3,331,936 7/1967 Owen ..200/168 C 3,562,468 2/1971 Stefani ..200/168 C 2 Clains, 7 Drawing Figures I 5 A Q 5 BACKGROUND OF THE INVENTION Field of the Invention This invention relates to a device for fixing a switch unit of a keyboard switch into the keyboard plate.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a device for fixing a switch unit of a keyboard switch easily onto the keyboard plate.

It is another object of the present invention to provide a device for fixing a switch unit of a keyboard switch which may be positively fixed onto the keyboard plate.

According to one aspect of the present invention, there is provided a device for fixing a switch unit of a keyboard switch. The switch unit comprises a rectangular piece having at least one stopper projected at one upper corner thereof, a knob engaging portion formed at the upper center thereof, and a pair of projections formed at opposite side surfaces thereof. The keyboard plate is formed in a U shape having a plurality of bridge portions and a pair of cutouts for engaging the projections of said switch unit therein. A keep leaf spring the used which has a center hole for turnably engaging the knob engaging portion of said switch unit and formed in length to be engaged under the bridge portions of said keyboard plate at opposite ends thereof when turned in the longitudinal direction of said keyboard plate. The keyboard switch, when assembled, comprises the switch unit fixedly held in the keyboard plate by the leaf spring.

BRIEF DESCRIPTION OF THE DRAWINGS These and other objects, features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of the switch unit of the device of the present invention.

FIG. 2 is a partial perspective view of the keyboard plate of the device of the present invention;

FIG. 3 is a perspective view of the keep leaf spring of the device of the present invention;

FIGS. 4A to 4C are plan views of the manner in which the switch unit is fixed to the keyboard plate, using the keep leaf spring; and

FIG. 5 is a partial sectional side view of the state of the device shown in FIG. 4C.

DESCRIPTION OF THE PREFERRED EMBODIMENT Reference is now made to the drawings, particularly the present invention contained in a frame, made of synthetic resin, etc., omitting the knob. The top surface of the switch unit 1 is lowered or recessed in the longitudinal direction thereof when it is engaged with a keyboard plate 3 shown in FIG. 2. The switch unit has a pair of stoppers l projecting at opposite corners on the upper surface of the switch unit 1. A knob engaging portion 2 is also formed on the upper surface at the center. Reference numeral 4 illustrates a pair of projections formed on both sides of the switch unit 1.

FIG. 2 shows the keyboard plate of thedevice of the present invention. The keyboard plate 3 is formed by dieing a flat plate and then bending it in a U shape so that a plurality of bridge portions 5 are formed on the upper portion thereof. Cutout portions 6' are formed on 1 both side surfaces of the keyboard plate 3 for engaging the projections 4 of the switch unit 1 between the respective bridge portions 5 of the keyboard plate 3. When the switch unit 1 is engaged between the bridge portions 5 of the keyboard plate 3, the projections 4 of the switch unit 1 are engaged with the cutout portions 6 of the keyboard plate 3. Thus, the switch unit is fixed with respect to forces in a downward direction (X direction in FIG. 2) and in a longitudinal direction (Y direction in FIG. 2) of the keyboard plate 3.

FIG. 3 shows the keep leaf spring of the device of the present invention, and the keep leaf spring 7 is formed substantially in elliptical shape and has a center hole 8 for tumably engaging the knob engaging portion 2 of the switch unit 1. Jig holes 9 are formed near both ends in a longitudinal axis thereof.

FIGS. 4A to 4C show the steps of fixing the switch unit to the keyboard plate using the keep leaf spring. When the switch unit 1 is fixed to the keyboard plate 3 of the device, the switch unit 1 is at first engaged with the keyboard plate 3 and the keep leaf spring 7 is rested on the top surface of the switch unit 1 so that thelongitudinal axis of the keep leaf spring 7 is directed in parallel with that of the bridge portions 5 of the keyboard plate 3 as shown in FIG. 4A. A jig (not shown) is engaged with the jig holes 9 of the leaf spring 7, and the jig is rotated clockwise as can be seen in FIG. 4B, and the leaf spring 7 is rotated continuously until the direction of the longitudinal axis of the leaf spring 7 contacts the stoppers 1' as shown in FIG. 4C. At this time, the longitudinal ends of the keep leaf spring 7 are engaged between the switch unit 1 and the bridge portions 5 of the keyboard plate 3 as shown. Since the upper surface of the switch unit 1 is recessed in a longitudinal direction of the keyboard plate 3, the keep leaf spring 7 is depressed onto the inclinations 1a and 1b forming recesses by both ends 7a and 7b provided in the short axis of the keep leaf spring 7 as shown in FIG. 5 so as to rigidly fix the switch unit in a downward direction. The keep leaf spring 7 itself cannot return without using the jig.

It should be understood from the foregoing description that since the device of this invention is thus constructed, the switch unit is simply mounted to the keyboard plate in a keyboard switch so as to enhance the operating efficiency at the same time it is positively fixed to the keyboard plate.

While the invention has been particularly shown and described with reference to the preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

I claim:

1. A device for fixing a switch unit into a keyboard switch comprising:

a. a rectangular switch unit having at least one stopper at one comer on the upper surface thereof, a knob engaging portion formed at the center of said upper surface, and a pair of projections formed on opposite side surfaces thereof;

a keyboard plate having a U shape with a'plurality of bridge portions forming the bottom of the U and a pair of cutout means for engaging the projections of said switch unit; and

. a keep leaf spring means having a center hole turnably engaging the knob engaging portion of said switch unit and having end portions for engagement under the bridge portions of said keyboard plateat opposite ends thereof when switch unit has a pair of stoppers projected at opposite upper comers thereof. 

1. A device for fixing a switch unit into a keyboard switch comprising: a. a rectangular switch unit having at least one stopper at one corner on the upper surface thereof, a knob engaging portion formed at the center of said upper surface, and a pair of projections formed on opposite side surfaces thereof; b. a keyboard plate having a U shape with a plurality of bridge portions forming the bottom of the U and a pair of cutout means for engaging the projections of said switch unit; and c. a keep leaf spring means having a center hole turnably engaging the knob engaging portion of said switch unit and having end portions for engagement undeR the bridge portions of said keyboard plate at opposite ends thereof when turned in the longitudinal direction of said keyboard plate, said leaf spring means fixedly holding said switch unit in said keyboard plate wherein said leaf spring means is held between said bridge portions and said stopper.
 2. A device as set forth in claim 1, wherein said switch unit has a pair of stoppers projected at opposite upper corners thereof. 